So BYO mag says we want pH 5.2-5.6 at MASH TEMP, not room temp.

[SpeedYellow]

And that if we measure at room temp, we need to subtract 0.35 from our readings. Isn't the consensus to target 5.2-5.6 at ROOM TEMP (and thus no correction is needed)? If so, it's perplexing that such a level of disagreement persists. 0.35 is quite a significant difference.

Here's the exact quote from this month's BYO (Mar-Apr) page 34:

When you dough in, the pH of the mash should settle into the 5.2 to 5.6 range (with the lower half of the range being preferable)...
...
If you heat any solution, its pH will drop. As such, if you take a sample from your mash and cool it to room temperature before taking a pH measurement, you will need to subtract 0.35 from your reading to account for the rise in pH that accompanied the cooling of the sample.

 

[mabrungard]

I prefer quoting 0.2 to 0.3 pH units due to the heating. There are some resources that recommend 0.35, but that would be dependent upon the temperatures. In general, that quoted mash pH range is at room temperature. If we were worried about what the actual pH of the mash at its mashing temperature (which we are not really concerned with), then the mashing pH range would be more like 5.0 to 5.4 at mashing temperature. It appears that there may be some confusion on the part of the author.

 

[Hermit]

We have a standardized testing procedure that has been verified to work by many. This figure does appear in the literature but AJ has gone through great pains to track this down and understand the issue.

 

[Kaiser]

Geez, I thought we were over that and the folks that write for BYO are knowledgeable enough to that the 5.2-5.6 target applies to a room temp sample.

I don't subscribe to BYO, so I should not be the one writing an e-mail about this.

Kai

 

[mabrungard]

I haven't seen the issue. Who is the author?

 

[Yooper]

I just recalled that I have a BYO subscription, but haven't even looked at it. I ran and grabbed it.

That is a very very long article (about 20 pages) from "BYO University" as the name of the series. They have a list of references, but not the actual author of each section. The entire section is attributed to Chris.

There are sections on "mashing", "packaging", etc.

However, when you read the "water chemistry and pH" section (this area) on page 34, it doesn't state at all that the pH should be taken at mash temp. It just states that when taking a reading at mash temp that: If you heat any solution, its pH will drop. As such, if you take a sample from your mash and cool it to room temperature before taking a pH measurement, you will need to subtract 0.35 from your reading to account for the rise in pH that accompanied the cooling of the sample.

That portion of the OP's post is NOT the same portion as the first part of his post: the pH of the mash should settle into the 5.2 to 5.6 range (with the lower half of the range being preferable)...

The author is NOT saying the mash pH should be 5.2-5.6 at mash temps and then have the reading subtracted. He's saying that your reading should be 5.2-5.6, and if you're taking the pH at mash temps to subtract .35 from THAT to get to the 5.2-5.6.

 

[SpeedYellow]

...The author is ... saying that your reading should be 5.2-5.6, and if you're taking the pH at mash temps to subtract .35 from THAT to get to the 5.2-5.6.

I think the quote from the article contradicts what you're saying:

As such, if you take a sample from your mash and cool it to room temperature before taking a pH measurement, you will need to subtract 0.35 from your reading to account for the rise in pH that accompanied the cooling of the sample.

For example, say you read a 5.35 at room temp. Per the article, this would correspond to 5.0 at mash temps. And per the article, since you measured at room temp, you need to subtract 0.35, so your 5.35 becomes 5.0. And this 5.0 pH is below the stated target of 5.2-5.6.

The authors never suggested taking the measurement at mash temps, and even noted (immediately following the OP's quote): "Cooling your sample is necessary for some pH meters and also helps prolong the life of the probe on many other models.".

 

[Yooper]

The article is very clear that 5.2-5.6 is the desired range. It's also very clear that mash pH is temperature dependent. It isn't the world's best written article, but if you read that paragraph a few times slowly, it's apparent that he is not saying what you claim you are reading.

 

[Hermit]

Whatever. When AJ first started posting I started googling because it certainly seemed like he knew what he was talking about and water was the last thing WELL outside my understanding. Others here have backed him up. I know my sources well enough on this one. My beer improved, at least in terms of repeatability and why some beers turned out the way they did finally made sense. I have access to a very expensive book that has the 3/3.5 figure in it. Again, bottom line though, we just need a repeatable procedure that works for us.

Knowledge and fine tuning always continue but I really don't believe that for the home brewer this will be turned on its head anytime soon. We have at least three people on this forum that are passionate about beer and know a lot about the water aspect. There are some differences but guess what? We all have different tastes and will like different water profiles. Go figure. I'm in the 'don't let the water show through' phase right now cuz I like me my malty beers. That might change. Who knows. At that point I might start aligning a little differently.

 

[Kaiser]

I was hoping that we can move away from the whole pH at mash temp discussion since it is somewhat irrelevant. I don't even think that the 0.35 pH shift is correct.

Kai